Track circuit system



May 26,1931.

A. G. WILLI AMS ON TRACK CIRCUIT SYSTEM Filed Feb. 5, 1.927 5 Sheets-Sheet l awvemtoz @511 (Mime 1;; v

May 26, 1931., A. G. WILLIAMSON I TRACK CIRCUIT SYSTEM Filed Feb. 5, 1927 5 Sheets-Sheet 2 May 26, 1931. A. G. WILLIAMSON TRACK CIRCUIT SYSTEM 5 Sheets-Sheet Filed Feb. 3, 1927 May 26, 1931. A. G. WILLIAMSON TRACK CIRCUIT SYSTEM 5 Sheets-Sheet 4 Filed Feb. 3, 1927 avwenboz 5 Sheets-Sheet 5 A. G. WILLIAMSON TRACK CIRCUIT S YSTEM Filed Feb. 5, 1927 May 26, 1931;

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maybe established including both rails of a track equipment.

invention is to provlde means whereby the Patented May 26, 1931 UNITED STATES PATENT OFFICE ABBA G. WILLIAMSON, OF CARNEGIE-PENNSYLVANIA, ASSTG'NOR, BY IvIESNE ASSIGN- MENTS, TO THE UNION SWITCH & SIGNAL COMPANY, OF SWISSVALE, PENNSYL- VANIA, A. CORPORATION OF PENNSYLVANIA a i TRACK CIRCUIT SYSTEM Application filed February 3,1927. Serial No. 165,603.

This invention relates to track circuit systems particularly for use in connection with train control systems of the type disclosed in Letters Patent No. 1,7 91,77 9 of February 5 10, 1931,.and. the present application is a continuation, in part, of application Ser. No. 549,663 filed April 5, 1922. The combination of trackway means to supply interrupted orperiodically varying current in combina- 0 tion with cab equipment controlled by the influence of such current is, however, not claimed herein but forms the subject matter of applicants copending application Ser. No.

215,318 filed August 25, 1927. V

In certain train control systems the train is provided with two pick-up circuits one of the indirect type and the other of the direct type and one of the main objects of this invention is to provide means where-by a circuit block and whereby also another circuit may be established between one or both rails and ground to properlycoordinate the indirect and direct pick-up circuits on the train with A further object of the circuit between one rail and ground is so arranged that existing track circuits may be used with but slight alteration. It will be 3o understood, however, that the invention is by no means limited to the above features but contains other and independent features of invention especially in connection with supplying an interrupted current to a trafiic track.

Certain features of the invention are claimed in application Seri No. 549668 filed April 5, 1922. y

In the accompanying drawings the invention is shown diagrammatically in several preferred forms. 7

Fig. 1 is a diagrammatic view showing one form of the invention.

Figs. 2, 3, 4 and 5 are diagrammatic views showing other forms ofthe invention.

Referring to Fig. 1, 1 and 2 represent the rails of a traiiic track divided into blocks, W, X, Y and Z in a manner well understood as by means of insulation 3. Thewayside sig- 0 nals which may or may not be used are indicated by San, S and S2 and as here shown armatures 143 and 152 of the block in rear. it

The current supplied for influencing the indirect and direct pick-up circuits of the train is supplied by a battery 110' and an interrupter 106 actuated by motor element 107.

The interrupted current supplied to thetwo' rails of the track and adapted to influence the indirect pick-up circuit of the train is impressed on the rails in the following manner. From batteryllO by wire 111, armature 112, wire 114, interrupter 106m, wire 115, resistance 116, lead 117, rail 1 of block X, across the train to rail 2, lead 118, wire 157, armature 120 and wire 121 back to battery 110. Bridging wires 115 and 118 is the primary 122 of a transformer 12300, the secondary 124 of which is interposed in a rail and ground circuit composed of said secondary Wire 125, resistance 126, wire 145 and ground on one side of said secondary; and wire 141, armature 143, wire 144 and wire 118 to rail 2 on the other side ofthe secondary. Rail 2 is not grounded but may in fact be insulated, that is to say the insulation is of course not perfect and there exists a leakage of current, but not an excessive one, so that voltage above ground potential is maintained on the rail. If the rail was actually grounded it would not be possible to maintain this voltage and consequently the direct pick-up circuit would not receive an impulse. This current will influence the direct pick-up circuit carried by the train. 109 indicates a relay controllng armatures 112 and 120 and this relay is normally deenergized so long as relay 151m of the succeeding block is energized. But when a train enters block X from block 1V relay 151a: will be deenergized thereby causing armatures 152 and 143 of relay 151% to drop. When this occurs a circuit is established through back contact 108: as follows battery 110w, wire 146, wire 155, relay 109, wire 153, back contact 108:, armature 152m, and wire 156 back to battery 110w. This picks up armatures 112 and 120 and cs tablishes a circuit through motor 107% as follows: from battery 110, wire 111, armature 112, wire 114, motor 10700, wire 157, armature 120 back to battery 110. It also establishes the previously described circuit through interrupter 106%. Thus when no train is in block X no current to affect either the indirect or the direct pick-up circuit is supplied.

lVhen a train enters block Y and a train K is present in block Z the rail and ground circuit is ruptured owing to the deenerigzation of relay 1512 and if the train enters block Z with another train already in the block no current will be received by said sec ond train.

In Fig. 2 is shown a trackway system to cooperate with two inductively coupled train carried circuits. In this form of the invention the usual track battery 15000 is connected to rail 1 by wire 160 and to rail 2 by wire 161, coil of relay 162a: and wire 163; track relay 15102 is connected to rails 1 and 2 by leads 164 and 165. The resistance of relay 162 is such that it does not interfere with the proper control of relay 151a: and is so adjusted that normal flow of current will not energize its coils sufliciently to lift armatures 166 and 167, but, when a train enters block X and relay 15100 is shunted the current flow will be sufliciently increased to cause relay 16200 to lift armatures 166 and 167. In this form of the invention the interrupting means are shown as being of the vibratory armature type and the motor elements are in the form of magnets. Motor element 168 of interrupter or vibrating armature 170 is energized by the following circuit: battery 110a, wire 169, armature 170, contact point 171, wire 172, coil of 168, wire 173, contact point 174, armature 167 when in lifted position and wire 175 back to battery 110m. The circuit just traced is normally open or ineffective on account of the normal deenergization of relay 162m. A normally ineffective or open circuit for supplying current, when a train enters the block, from the source through interrupter 17 0 to the rails of block X in series is as follows: battery 110:0, wire 169. vibrating armature or interrupter 170, contact 171,wire 172, wire 176, resistance 177,wires 178 and 160, rail 1, train shunt, rail 2, wires 163, 179 and 173, contact 174, armature 167 and wire 175 baclr to battery 1100:.

Motor element 184 of the second interrupter or vibrating armature 181 is energized by the following circuit: battery 110m, wires 169 and 180.. vibrating armature 181, contact point 182, wire 188, coil of 184, wire 185, contact 186 of track relay 1513 wires 187 and 178, contact 174, armature 167 and wire 175 back to battery 11000. It will be noted that this circuit is controlled not only by relay 16200 but also by track relay 1511 of the block in advance, and this circuit normally open or ineffective on account of the normal deenergization of relay 162m and is likewise open when the block (Y) in advance is occupied by a train. A normally open or ineifective circuit for supplying current, when a train enters the block and the block in advance is not occupied, from the source through interrupter 181 i to the w rails of block X in parallel is as follows: battery 110w, wires 169 and 180, armature l81,-wires 183 and 188, armature 189 of relay 15ly, wire 191, center tap of resistance 192, rails 1 and 2 in parallel, resistance 193, center tap of same, wire 194, contact 195, armature 166 of relay 162 when in the lifted position and wires 196 and 175 back to battery 110%.

Thus, when a'train enters block X, relay 162:0 is energized sufficiently to lift its armatures and two interrupted currents are supplied to the rails, one through interrupter 170 to the rails in series and the other through f interrupter 181to the rails in parallel.

the block in advance, Y, is occupied and relay 151 is deenergized the current to the'rails in parallel is not sufficient, and if a train enters a block that is already occupied by another train the current to the rails in series will be shunted by the train occupying the block and the second train will receive no current from the circuit including the rails in series.

In Fig. 3 is shown a modification in which alternating current is employed. As there shown, a transformer Tm, in the case of block X, is used the secondary 292 of which is connected to rails 1 and 2 at the outgoing end of block X and whose primary 294 receives power from line wires 295 and 296, the latter being fed by generator G. Between primary 294 and the transmission line is shown a pole changer 197 which is operated by mechanism, indicated by the dotted line,'frorn a wayside signal as Sy. This part of the system need not be used in connection with the train control circuits and need not, therefore, be described eXcept to say that the wayside signal is of the three position type, and that pole changer 197 is used to reverse the polarity of the normal track circuit current. 2930: indicates a track relay connected to the rails at the ingoing end of block X in a well known manner. Va; indicates another transformer, the primary 199 of which is energized as follows transmission line 296, wire 198, winding 190, wire 200, armature 201 of track relay 293m of block X, back contact 202 and wire 203 to transmission line 295. The circuit just traced is therefore normally ineffective or open. Secondary winding 204 of Van is included in a circuit that includes motor element 206 to actuate interrupter or vibrating armature 205, which latter preferably makes use of the vibrating reed principle that is so commonly employed in rectifiersfor battery chargers. The vibrating armature or interrupter is'included in the following circuit:

secondary 204, wire 207, armature 208 of track relay 293g of the block in advance, contact 209, wire 210, rail 2 of block X, train shunt, rail 1, wire 211, impedance coil 212, wire 213, contact 214, interrupter or vibrating armature 205 and back to secondary 204. Thus whenever a train enters block X and shunts relay 29300 a circuit is closed through primary revolving armature type actuated by motor 305, wire 306, front contact 307,

element 304. When a train enters block X and shunts track relay 293% then relay 302 at the outgoing end of the block will be energized andthe following circuit will be established through motor element 304: secondary wire 308, motor element 304, wire 309, front contact 310, and wire 311 back to secondary 305. Another circuit through the interrupter will also be established as follows: secondary 305, wire 306, front contact 307, wire 308, interrupter 303, wire 312, rail 1 of block X, train shunt, rail 2, wire 313, front contact 314 and 'wires 315 and 311 back to secondary 305. If

the block in advance, Y, is occupied and relay 29311 is deenergized then relay 302 will likewise be deenergized so that the circuit through the interrupter to the rails remains open. If a second train enters a block already occupied then this second train will receive no current.

In Fig. 5 a further modification of the invention is shown. Here the track circuit is of the direct current type and is supplied by a battery as 316. When a train enters block X from the right and shunts the track relay then relay 317 at the outgoing end becomes energized and will disconnect track battery 316 from the rails at the back contacts 318 and 319. The energization of relay 317 will close circuits from primary 322 oftransformer Tm through motor element 320 and interrupter 321 as will be apparent, and will also close a circuit from secondary 323 of transformer Tm to the rails. The interrupter will cause an interrupted current to flow in primary 322 and this, in turn, will be induced in secondary 323 and the latter will then supply the interrupted current to the rails by way of the following circuit: sec

ondary 323, wire 324, front contact 325, wire 326, rail 1, train shunt, rail 2, wire 327, front contact 328 and wire 329 back to secondary 323' Thus the interrupter included in the circuit of the primary controls or influences or modifies the current flowing in the secondary.

By the expression pulsating current used in the accompanying claimsit is intended to lng current or an interrupted or fluctuating direct current, and by an interrupted currentis meant either a direct or an alternating interrupted current.

The feature of disconnectingthe track bat- So likewise, the specific form disclosed in Fig. 5 hereof is not specifically claimed herein but forms the subject matter of applicants copending application Ser. No. 516,886 filed February 19, 1931.

I claim 1. A track circuit system comprising: traffic rails divided into blocks, a source of current, a circuit including both rails of a block, a circuit between ground and at least one of said rails, and an interrupter for supplying an interrupted'current to said circuits from said current source.

2. A track circuit system comprising: traffic rails divided into blocks, a source of current, an interrupter connected to said source, a circuit including both rails of a block fed by saidinterrupter and source, a circuit between ground and at least one of said rails,

and a transformer between said first and said second circuit.

3. A track circuit system comprising: traffic rails divided into blocks, a source of current, a circuit including both rails of a block, a circuit between ground and at least one of said rails, means for supplying a pulsating current to said circuits from said current source, and a relay controlled by trafiic in a preceding block for controlling the circuit between rail and ground.

4. A track circuitsystem comprising: traflic rails divided into blocks, a source of current, a circuit including both rails of a block, a circuit between ground and at least one of said rails, an interrupter for supplying an interrupted current to said circuits from said current source, and a relay controlled by traffic in a preceding block for controlling the current between rail and ground.

5. A track circuit system comprising: traffic rails divided into blocks, a source of current, an interrupter connected to said source, a circuit including both rails of a block fed by said interrupter and source, a circuit becornprehend both an alternating or oscillat---.

tween ground and at least one of said rails,

a transformer between said first and said second circuit and a relay controlled by traffic in a preceding block for controlling the circuit between rail and ground.

6. A track circuit system comprising: traffie rails divided into blocks, a source of current, a motor, an interrupter driven by said motor, a circuit including said source and motor but normally ruptured, a circuit including said source, both rails and the inter rupter but normally ruptured, and means for completing said circuits when a train enters a block.

7. A track circuit system comprising: traftic rails divided into blocks, a source of current, a motor, an interrupter driven by said motor, a circuit including said source and motor but normally ruptured, a circuit including said source, both rails and the interrupter but normally ruptured, a circuit between ground and at least one of said rails, fed from the circuit passing through the interrupter, and means for completing the circuits through the motor and interrupter when a train enters a block.

8. A track circuit system comprising: traffic rails divided into blocks, a source of current, a motor, an interrupter driven by said motor, a circuit including said source and motor but normally ruptured, a circuit including said source, both rails and the interrupter, and means for completing the circuit through the source and motor when a train enters a block.

9. Atrack circuit systemcomprising: trafiic rails divided into blocks, a source oi. current, a motor, an interrupter driven by said motor, a circuit including said motor and source but normally ruptured, a circuit including said source, both rails and the interrupter, a circuit, between ground and at least one of said rails, fed from the circuit passing through the interrupter, and meansfor completing the circuit through the source and motor when a train enters a block.

10. A track circuit system comprising: traffic rails divided into blocks, a source of current, a motor, an interrupter driven by said motor, a circuit including said source and motor but normally ruptured, a circuit ineluding said source, both rails and the interrupter but normally ruptured, a circuit, be-

tween ground and at least one of said rails, fed from the circuit passing through the interrupter, means for completing the circuits through the motor and interrupter when a trainenters a block, and a relay controlled by traffic in a preceding block for controlling the circuit between rail and ground.

11. A track circuit system comprising: traflic rails divided into blocks, a source of current, a motor, an interrupter driven by said motor, a circuit including said source and vvmotor but normally ruptured, a circuit including said source, both rails and the interrupter, a circuit between ground and at least one of said rails, means for completing the circuit through the source and motor when a train enters a block, and a relay controlled by traffic in a preceding block for controlling the circuit between rail and ground.

12. A track circuit system comprising: traific rails divided into blocks, a source of current, a motor, an interrupter driven by said motor, a circuit including said motor and source but normally ruptured, a circuit including said source, both rails and the interrupter, a circuit between ground and at least one of said rails, fed from the circuit passing through the interrupter, means for completing the circuit through the source and motor when a train enters a block and a relay controlled by trafiic in a preceding block for controlling the circuit between rail and ground.

13. A track circuit system comprlsmg:

trafic rails divided into blocks, a normally charged track circuit, a track relay controlled by said track circuit, a source of current, a motor, an interrupter driven by said motor, a circuit including said source and motor but normally ruptured when said relay of the local block is energized, a circuit including said source, both rails and the interrupter, a circuit between ground and at least one of said rails, fed from the circuit passing through the interrupter, and controlled by the track relay of the preceding block.

14. A track circuit system comprising: traflic rails divided into blocks, a normally charged track circuit, a track relay controlled by said track circuit, a source of current, a motor, an interrupter driven by the motor, a circuit including said source and motor but normally ruptured when the track relay of the local block is energized, a circuit includin g said source, both rails and the interrupter also normally ruptured when the track relay of the local block is energized, and a circuit between ground and at least one of said rails fed from the circuit passing through the interrupter and controlled by the track relay of the preceding block.

15. A track circuit system comprising: trafiic rails divided into blocks, a track battery, leads connecting said battery to the rails, a track relay connected to the rails, a direct current source, an interrupter, a circuit includin said source and interrupter connected to the leads from the track battery, a second circuit, controlled by the track relay of the preceding block, connected to one of the leads of the local track battery and to ground, and a transformer between the second circuit and the circuit passing through the interrupter.

16. A track circuit system comprising: traflic rails divided into blocks, a track battery, leads connecting said battery to the rails, a track relay connected to the rails, a direct current source, an interrupter, a circuit, controlled by the track relay of the local block and normally incomplete so long as said track relay is energized, including said source and interrupter and connected to the leads from the track battery, a second circuit, controlled by the track relay of the preceding block, connected to one of the leads of the local track battery and to ground, and a transformer between the second circuit and the circuit passing-through the interrupter.

17. A traflic circuit system including: trafiic rails arranged in blocks, circuit means, including the traflic rails and an interrupter, normally ineffective to supply current to said rails, a motor, to actuate the interrupter, normally deenergized, and means, to energize the motor with non-interrupted current, and to render the said circuit means effective to supply interrupted current to the rails of a block in response to the entrance of a train into the block.

18. A traific circuit system including: traffic rails arranged in blocks, circuit means, including the trafiic rails and an interrupter, normally inefiective to supply current to said rails, a motor, to actuate the interrupter, normally deenergized, and a track circuit, which when shunted by the entrance of a train into a block, causes the motor to become energized with non-interrupted current and renders the first circuit means effective to supply interrupted current to the rails of said block. 7

19. A track circuit system including: traffic rails arranged in blocks, a source of current to be connected across the trafiic rails at the exit end of the block, a relay for each block which when energized connects said current source to the rails, and circuit means to energize said relay in response to the entry of a train into the block.

20. A track circuit system including: traffic rails arranged in blocks, a source of current to be connected across the traffic rails at the exit end of the block, a relay for each block which when energized connects said current source to the rails, and a track relay at the entrance end of a block which when shunted by the entry of a train into the block energizes said first-mentioned relay.

21. A trafiic circuit system including: traffic rails arranged in blocks, circuit means, including the traffic rails and an interrupter, normally ineffective to supply current to the rails of a block, a motor, to actuate said in terrupter, a circuit for said motor normally inefi'ective to energize it, a relay for each block which when energized renders said motor circuit effective to energize the motor and renders the first circuit means effective to supply current to the rails of a block, and other circuit means to energize said relay in response to the entry of a train into the block.

22. A trafiic circuit system including: traffic rails arranged in blocks, circuit means, in-

cluding the trafiic rails and an interrupter, normally ineffective to supply current to the rails of a block, a motor, to actuate said interrupter, a circuit for said motor normally ineffective to energize it, a relay for each block which when energized renders said motor circuit effective to energize the motor and renders the first circuit means effective to supply current to the rails of a block, and a track relay which when shunted by the entry of a train into the block energizes said first-mentioned relay.

23. A track circuit system including: trafzic rails arranged in blocks, a normally closed track circuit for each block including the traffic rails, a source of current and a track relay, another circuit for each block to control the supply of train controlling current across the trafiic rails at the exit end of the block, and a second relay for each block, under the control of the track relay of the same block, to open said other circuit when the track relay is energized and to close said other circuit when the track relay is deenergized.

24. In combination, a section of railway track, a normally open circuit including an electromagnetic device, a second circuit controlled by said device for supplying periodically interrupted train governing current to the rails of saidsection, and means for closing said first circuit when a train enters said section.

25. In combination, a section of railway track, a normally open circuit including an electromagnetic device, a second circuit controlled by said device for supplying periodically interrupted train governing current to the rails of said section, a track circuit including a track relay for said section, and means for closing said first circuit when said track relay is deenergized.

26. In combination, a section of railway track, a track circuit including a source of current and a track relay for said section, a normally open circuit including a back contact of said track relay and an electromagnetic device, and a third circuit controlled by said device for supplying periodically interrupted train governing current to the rails of said section.

Signed at Pittsburgh, in the county of Allegheny, and State of Pennsylvania, this 1st day of February, 1927.

ABBA G. WILLIAMSON. 

